Effect of a pharmacist intervention on clinically important medication errors after hospital discharge: a randomized trial

Abstract

Background: Clinically important medication errors are common after hospital discharge. They include preventable or ameliorable adverse drug events (ADEs), as well as medication discrepancies or nonadherence with high potential for future harm (potential ADEs).

Objective: To determine the effect of a tailored intervention on the occurrence of clinically important medication errors after hospital discharge.

Design: Randomized, controlled trial with concealed allocation and blinded outcome assessors. (ClinicalTrials.gov registration number: NCT00632021)

Setting: Two tertiary care academic hospitals.

Patients: Adults hospitalized with acute coronary syndromes or acute decompensated heart failure.

Intervention: Pharmacist-assisted medication reconciliation, inpatient pharmacist counseling, low-literacy adherence aids, and individualized telephone follow-up after discharge.

Measurements: The primary outcome was the number of clinically important medication errors per patient during the first 30 days after hospital discharge. Secondary outcomes included preventable or ameliorable ADEs, as well as potential ADEs.

Results: Among 851 participants, 432 (50.8%) had 1 or more clinically important medication errors; 22.9% of such errors were judged to be serious and 1.8% life-threatening. Adverse drug events occurred in 258 patients (30.3%) and potential ADEs in 253 patients (29.7%). The intervention did not significantly alter the per-patient number of clinically important medication errors (unadjusted incidence rate ratio, 0.92 [95% CI, 0.77 to 1.10]) or ADEs (unadjusted incidence rate ratio, 1.09 [CI, 0.86 to 1.39]). Patients in the intervention group tended to have fewer potential ADEs (unadjusted incidence rate ratio, 0.80 [CI, 0.61 to 1.04]).

Limitation: The characteristics of the study hospitals and participants may limit generalizability.

Conclusion: Clinically important medication errors were present among one half of patients after hospital discharge and were not significantly reduced by a health-literacy-sensitive, pharmacist-delivered intervention.

Primary funding source: National Heart, Lung, and Blood Institute.

Figure 1

Flow diagram.

Figure 2

Adjusted treatment effect on clinically important medication errors, ADEs, and potential ADEs, by subgroups of interest. Panel A – Clinically important medication errors; Panel B – ADEs; Panel C – Potential ADEs Incidence Rate Ratios (IRR) are presented. Values < 1 indicate that the mean count of outcomes in the treatment group is smaller than the mean count in the usual care group. * P-values for the main treatment effect are based on negative binomial regression models, adjusted for covariates, using multiple imputation for missing predictor data. † P-values for the interactions assess homogeneity among subgroup specific treatment effects and are based on the likelihood ratio test comparing models with and without the interaction term.